Re: c/8411: Segmentation fault error in malloc

Re: c/8411: Segmentation fault error in malloc

[neroden]

Synopsis: Segmentation fault error in malloc

State-Changed-From-To: feedback->closed
State-Changed-By: neroden
State-Changed-When: Sun Feb 23 21:06:03 2003
State-Changed-Why:
    No feedback > 3 mo., probably user error, example code too big.

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8411

Re: c/8411: Segmentation fault error in malloc

[Joe Buck]

The following reply was made to PR c/8411; it has been noted by GNATS.

From: Joe Buck <jbuck@synopsys.com>
To: gcc-gnats@gcc.gnu.org, bridean@ureach.com, gcc-bugs@gcc.gnu.org
Cc:  
Subject: Re: c/8411: Segmentation fault error in malloc
Date: Thu, 31 Oct 2002 14:33:42 -0800

 http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8411
 
 Have you checked this program with a memory-checking tool (electric fence,
 valgrind, purify, etc) and verified that it doesn't have any memory 
 allocation
 errors (e.g. double-frees, writing beyond the end of an allocated 
 object, etc.).
 The most common cause of segmentation faults in malloc is this kind of 
 user error,
 and the problems tend to show up differently depending on optimization.
 

Re: c/8411: Segmentation fault error in malloc

[jbuck]

Synopsis: Segmentation fault error in malloc

State-Changed-From-To: open->feedback
State-Changed-By: jbuck
State-Changed-When: Thu Oct 31 14:34:20 2002
State-Changed-Why:
    waiting for more info from user: not our job to debug
    uses of malloc/free

http://gcc.gnu.org/cgi-bin/gnatsweb.pl?cmd=view%20audit-trail&database=gcc&pr=8411

c/8411: Segmentation fault error in malloc

[bridean]

>Number:         8411
>Category:       c
>Synopsis:       Segmentation fault error in malloc
>Confidential:   no
>Severity:       critical
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Thu Oct 31 02:16:01 PST 2002
>Closed-Date:
>Last-Modified:
>Originator:     Brian M. Dean
>Release:        unknown-1.0
>Organization:
>Environment:
Red Hat 8.0  Gnu compiler 3.2
>Description:
When the following program is compiled with -O3 optimization
either
int CheckRepeats[MaxRepSize * sizeof(int)]
or
CheckRepeats = (int *) malloc(MaxRepSize * sizeof(int))
Will return a segmentation fault.

If the program is compiled without optimization, it will execute normally.
>How-To-Repeat:
Do the following compile
gcc -O3 -o GetComplete GetComplete3.c
Then run it as follows
./GetComplete 3 -1000 1000
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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Content-Disposition: attachment; filename="GetComplete3.c"

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